Crafting is an in-game system allowing players to create specific items, such as a weapon, hat or materials for further crafting, using unwanted or duplicate items gained normally via the Item drop system. To create these items, the player must follow explicit blueprints, some of which are initially available and others of which must be discovered by the player by experimentation. After following a valid, undiscovered blueprint recipe, the player will both gain the item specified by the blueprint, and the blueprint will be added to the player's list of known blueprints. If the player attempts to craft an item without a corresponding blueprint, they will be notified that no such recipe exists, and no items will be lost.

†The Smelt Class Weapons blueprint was originally one Primary, Secondary, and Melee weapon of each class, but was then altered to allow any 3 (now 2) weapons from the same class, to accommodate the Sniper and Spy, who only had items for two loadout slots when the Sniper vs. Spy Update launched. This has made the blueprints marked with a "†" superfluous.

Note: If one provides 3 identical weapons, one is given the option of creating a Class Token or a Slot Token, but not both.Additionally, if one provides a Pain Train with a Class Token, or 3 Pain Trains and chooses to create a Class Token, this will always result in a Soldier Token, never a Demoman Token.

†Rebuilding headgear does not work for Cheater's Lament, Ghastly Gibus, Ghastlier Gibus, Max's Severed Head, Bill's Hat, Dealer's Visor, The Mann Co. Cap, Ellis' Cap or Alien Swarm Parasite. Additionally, unlike other misc. items, the Service medal, and OSX earbuds do not work. Rebuilding Headgear is also not possible with hats bought from the Mann Co. Store.

‡Both the level of the Batter's helmet, as well as the color is not retained when crafted into a Bonk helm. The level will be randomized and the color will be returned to normal, even though it is the same helmet with Bonk drinks attached to the sides.

Note:Any unusual metal scraps obtained from servers after the halloween patch gives you an untradable loan modification metal. This metal can still be used to craft the voodoo juju,chilling skull and the headless horseman's head taker but it will be untradable.

Crafting weapon classifications

Contrasting the weapon slots in-game, the crafting system classifies some weapons in different slots. An example of this is the Spy's Revolver, which is not a primary weapon contrary to it being in the first slot in-game. Below is a list of all the usable weapons and what slots the crafting system uses. Note that the table does not include the stock weapons for the classes, such as the Scattergun, as these are not usable in crafting.

Golden Wrench

From July 5 to July 9, 2010, players crafting any items in-game had the chance of finding 1 of 100 of an extremely rare item, the Golden Wrench. A series of times when a Wrench was designed to drop was utilized by Valve, and when a player crafted an item after one of these times, a random drop could occur giving the player their crafted item and a Golden Wrench. When a Wrench was found, it would be announced to all online Team Fortress 2 servers at once in the form of a dialogue box in the center of the screen and an accompanying soundbite. This was only available before and leading up to the Engineer update, until all 100 wrenches were found. An announcement was also shown when one of these wrenches was destroyed. These wrenches have the ability to turn ragdolls into gold statues, but are otherwise identical to the default Wrench.

Due to this event, the Smelt Reclaimed and Refined Metal blueprints were temporarily disabled until all of the 100 Golden Wrenches had been acquired, to stop people from endlessly smelting and re-crafting their Metal until they got one. These blueprints were disabled up until the Mann-Conomy Update, even though the Engineer Update was completed and no Golden Wrenches could be found.

The recipe for Scrap Metal was previously 3 primary, secondary, or melee weapons.

When Miscellaneous items were first separated from Hats, due to players wanting to equip the Camera Beard and other Spy hats simultaneously, the Camera Beard began dropping at the same rate as weapons. It was not unusual for players to find many in the course of a week. Despite the Camera Beard being considered as a 'headgear', two could not be combined to get another hat but could be crafted together to create another Miscellaneous piece of headgear. After the Camera Beard drop-rate was patched in a subsequent update, it became possible to craft two of them together to make a hat.

Grenade, Building, Head, and PDA(1) Slot Tokens were once listed in the items_game.txt file and were valid items, but none of them were given blueprints, and as such these items were removed from the game during the Mann-Conomy Update. It was previously possible to craft a Head Slot Token by placing 4 hats in the crafting window due to an oversight, but the blueprint and all instances of the item were finally removed when the Mann-Conomy update was launched (For example, this backpack before and after the update).

Some cases have been reported of players "finding" scrap metal. This is most likely the cause of the player losing connection to Steam after clicking the craft button. This means the items are used in the craft recipe, yet the result of the craft remains uncollected until the player dies in a server: giving the "PLAYERNAME has found: METALTYPE" alert.

When crafting, if metals or items disappear unexpectedly, a fast method of making them re-appear is to access the main menu and enter the Mann Co. Store.

Robin Walker confirmed that all items seen in the store (with the exception of Crate Keys, Secret Saxton and Pile o' Gifts) can randomly drop in-game. [1] (This is no longer true as of the Scream Fortress event; the Spine-Chilling Skull and Voodoo Juju are both listed in the store as being unobtainable via random drop. They can, however, be crafted with items available via random drop.)

All weapons or hats purchased in the Mann Co. Store are uncraftable and untradable; though as of the October 6, 2010 Patch all items marked as "Store Promotion" were made craftable but not tradable. Anything crafted with a Store Promotion item will be itself untradable.

Items gained via achievements before the Mann-Conomy update were temporarily uncraftable and untradable, but this was changed shortly after so that they could be crafted although they are still untradable.

If an untradable item is used in the crafting of a hat, weapon or item, then the resulting item will also be untradable.

Untradable metal, and items made with untradable metal, have reverted to tradable, when the next patch was released due to a glitch. This behavior was observed during the Scream Fortress event with Voodoo Jujus and Spine-Chilling Skulls crafted using untradable Haunted Metal Scrap. Halloween Hats crafted prior to the November 10, 2010 Patch became tradable after the update, but hats crafted after that have reportedly remained untradable, suggesting Valve has fixed the glitch.